1. Field of the Invention
This invention relates to a touch panel, especially to an on-cell capacitive touch panel having appropriately designed touch sensor patterns capable of effectively suppressing the generation of reverse signals without cover lens and optical clear adhesive (OCA)/optical clear resin (OCR) to avoid poor multi-touch sensing.
2. Description of the Related Art
In general, the laminated structures of capacitive touch panels can be divided into several types. Among these types, the on-cell capacitive touch panel includes a touch sensor layer disposed on the glass of the display panel and has an advantage of display and touch integration to achieve the effect of light and thin. Users can directly perform a touch operation on the display panel of the electronic product without cover lens.
Please refer to FIG. 1 and FIG. 2. FIG. 1 and FIG. 2 illustrate two different laminated structures of the on-cell capacitive touch panel respectively. The difference between the laminated structure 1 of FIG. 1 and the laminated structure 2 of FIG. 2 is that the laminated structure 1 of FIG. 1 includes cover lens 18 and optical clear adhesive (OCA)/optical clear resin (OCR) 16, but the laminated structure 2 of FIG. 2 does not include them.
Although the laminated structure 2 of FIG. 2 without the cover lens and the OCA/OCR can achieve effects of simplifying laminated structure, reducing thickness, and saving costs, stronger reverse signals will be generated and multi-touch sensing of the touch panel will become poor.
For example, as shown in FIG. 3, two touch points P1 and P2 are located at the upper left corner and the upper right corner of the touch panel TP having the laminated structure 2 instead of being located at the same axis, and reverse signals are generated at a first location R1 of the lower left corner of the touch panel TP and a second location R2 of the lower right corner of the touch panel TP. Therefore, the touch signals at the two touch points P1 and P2 will not be canceled out by the reverse signals.
However, as shown in FIG. 4, two touch points P3 and P4 are located at the same axis of the touch panel TP having the laminated structure 2, and reverse signals are generated at locations R3 and R4 overlapping the two touch points P1 and P2. Therefore, the touch signals at the two touch points P3 and P4 will be canceled out by the reverse signals and multi-touch sensing of the touch panel TP will become poor.
Therefore, the invention provides an on-cell capacitive touch panel to solve the above-mentioned problems.